araspai wrote:

A large cube 10cm on a side is composed of smaller cubes 1 cm on a side. The large cube is printed red on its outside surfaces and then all the cubes are mixed in a drum. If one cube is selected randomly, which of the following is the approximate probability that the cube will have at least one red face?

A) 1:6

B) 1:5

C) 1:4

D) 1:3

E) 1:2

P(atleast one red face) = 1 - P(no red face)

The unpainted "area of the cube" is 8*8*8

the total area = 10* 10*10

P(No reds) = 512/1000

P(atleast one red face) = 488/1000

Approximately 1:2

thanks

praetorian